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bioRxiv · 10.1101/2025.07.26.666132

Processing and sectioning of organ donor spinal cord tissue for electrophysiology on acute human spinal cord slices

Abstract

Acute spinal cord slice electrophysiology is a powerful technique used in preclinical basic science research to investigate sensory and motor neuron function and pathophysiology. A major barrier that stands between implementing these findings into effective clinical treatments is the translational gap between rodent models and human patients. To date, no methods or protocols describe how to prepare viable human spinal cord slices for acute electrophysiological recordings. To bridge this translational divide, we describe here a protocol for the extraction of spinal cord tissue from consenting human organ donors and the preparation and sectioning of this tissue for acute spinal cord slice electrophysiology. With the collaboration of a transplant service and licensed surgeon, tissue can be extracted in 30-50 minutes. Acute spinal cord slices can then be prepared in the laboratory by trained graduate students in 2.5-5 hours, depending on the amount of tissue and scope of experiments. Using a viability stain to confirm that spinal slices are of sufficient quality to proceed, slices can then be used for either patch-clamp recordings to study the excitability of individual neurons or for high-density multielectrode array recordings to study intact sensory circuits. Slices remain viable for 4 to 8 hours, providing ample time for investigating synaptic and circuit-level signalling dynamics, including the use of pharmacological agents to probe the roles of specific molecular targets. The approaches described here can be implemented to improve translational physiological research and as a human tissue-based preclinical drug target identification and validation assay.

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BibTeXRIS

Dedek, A., Gambeta, E., Shriraam, R., Topcu, E., McDermott, J. S., Krajewski, J. L., Tsai, E. C., Hildebrand, M. E.. 2025-07-31. Processing and sectioning of organ donor spinal cord tissue for electrophysiology on acute human spinal cord slices. https://doi.org/10.1101/2025.07.26.666132

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